Arnold School of Public Health researcher gets $3.7-million grant to study sleep loss

Contact: Margaret Lamb 803.777.5400; Margaret@mailbox.sc.edu

Most of us spend about one-third of our lives sleeping, but as we age, we sleep less and appear to need less shut-eye.

A University of South Carolina researcher is beginning a national study to see just how much, or little, sleep people between the ages of 60 and 80 really need to remain physically and mentally healthy. With a $3.7 million grant from the National Institutes of Health, Dr. Shawn

Youngstedt, an exercise science professor in the Arnold School of Public Health, is collaborating with researchers at UCLA, State University of New York Downstate and the University of Arizona to study the effects of spending one hour less in bed. Specifically, the researchers will measure inflammation, sleepiness, body weight, mood, blood glucose regulation, quality of life, incidence of acute and chronic illness, and frequency of automobile accidents.

“The amount of sleep older people need is an ongoing topic for debate,” Youngstedt said. “Some scientists believe that older adults are particularly vulnerable to the negative effects of sleep loss. Other scientists argue that many older adults spend too much time in bed and that moderate reduction of time in bed could improve sleep quality and promote health and longevity, particularly for ‘long’ sleepers.”

Youngstedt and his team will study 200 individuals for five years. Half of the participants will be drawn from a group that sleeps eight to nine hours, and the other half will comprise individuals who typically get six to 7¼ hours of sleep each night.

In contrast, most sleep restriction data are gathered from studies of people who suffer from extreme sleep deprivation, typically 24 to 72 hours. “We want to look at what far more people experience, and that is moderate sleep loss,” Youngstedt said.

Participants will fill out daily questionnaires and undergo extensive monitoring by a medical team. Anthropologists will interview the longer sleepers to try to determine why some people sleep longer than others.

Youngstedt’s previous research has shown that people typically don’t experience negative side effects from moderate sleep loss.

“There is tremendous publicity about our being a sleep-deprived society and that sleep loss explains so many ills, such as obesity and diabetes, Youngstedt said. “We think that this notion is grossly exaggerated. Spending too much time in bed leads to fragmented sleep. We think less time in bed, or restricted sleep might actually lead to better sleep.”